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Ecology for a social revolution : re-defining the role of ecological and environmental science professionals and their responsibilities towards society
No full textThe sixth mass extinction and the ongoing biodiversity and climate crises demand urgent action from ecologists and environmental scientists (EESs). Despite their critical role in addressing these challenges, EESs face unclear professional responsibilities towards society, local communities and ecosystems. The 2024 ANdiNA workshop was held in Conguillío National Park in Chile, within Wallmapu the ancestral land of the Mapuche people. It gathered global EESs to explore the roles, obligations and accountability of professionals in this field. The discussions focused on the evolving responsibilities of EESs amidst the environmental crises, as well as the need for clearer frameworks to guide their actions.Key questions included the scope of EESs' professional activities, how their obligations should adapt during times of crisis and whether they should be held accountable for scientific mistakes that lead to negative societal outcomes. The workshop explored the potential for creating a codified framework, such as an oath or manifesto, to clarify EESs' professional responsibilities. Participants highlighted the importance of integrating financial, intellectual, ethical and institutional dimensions in defining these roles, particularly in how EESs engage with local communities and society.Emerging themes included the need for a shared framework to align EESs' actions, exemplified by the Conguillío Statement, which encourages collaboration, inclusivity and ethical engagement with communities, especially Indigenous ones. The workshop also emphasised the importance of solution-orientated, transformative research and advocacy, calling for a shift in how EESs approach their roles as agents of change. By critically reflecting on their responsibilities, the workshop provided a foundation for re-imagining the role of EESs in the face of global environmental crises, urging systemic, collaborative approaches to safeguarding both nature and humanity
Just institutions or just institutions? Research on groundwater justice in the European Union
No full textThis qualitative systematic literature review examines discussions on groundwater justice in the European Union (EU) by analyzing 51 peer-reviewed academic articles that address groundwater governance and justice-related issues. The review identifies a limited number of studies that explicitly focus on groundwater justice, with most research emphasizing the local and regional institutional setup for groundwater distribution, particularly in agricultural contexts in Spain and France. Key themes in the literature include the role of institutions in regulating groundwater distribution, decision-making processes, and the recognition of different forms of knowledge. The literature also examines groundwater markets, often in relation to their potential to exacerbate inequalities, and explores the historical development of groundwater rights regimes, highlighting their continued influence on governance and water rights regimes. Additionally, studies discuss how infrastructure investments can further amplify inequalities, particularly as groundwater levels decline.The limited explicit focus on groundwater justice in the EU may be linked to disciplinary traditions in commons scholarship and environmental justice research that tend to focus on institutions and high-profile cases of injustices, respectively. This paper highlights how grounded justice perspectives from EJ and Water justice literature based on capabilities and power can analyze more subtle cases of injustice. The review suggests that integrating uncertainty as an analytical category might be fruitful for groundwater justice research since uncertainties regarding groundwater materiality and modelling ultimately influence institutions mediating groundwater access and decision-making processes. Future research could therefore explore the relationship between uncertainty and justice, specifically how uncertainties shape groundwater rights distributions and decision-making processes
Psychometric considerations in assessing fear generalization as a predictor of anxiety
No full textBackgroundThe ability to adaptively transfer acquired fear to novel situations is fundamental for survival in ever-changing environments and may contribute to the emergence and persistence of anxiety disorders. Consequently, research has focused on the assessment of fear generalization profiles to predict individual differences in anxiety. However, substantial heterogeneity in the operationalization of generalization hampers comparisons across studies and poses a risk to the replicability of findings.MethodsTo address these issues, we reviewed the literature to identify commonly used methods for characterizing perceptual fear generalization profiles. Then, we conducted simulation analyses to examine correlations between indices and probe their robustness against measurement noise. Finally, we used 2 large empirical datasets (N = 1175 and N = 256 healthy humans) to examine the reliability of these indices and their validity in predicting anxiety-related traits.ResultsAll identified indices were substantially correlated but highly sensitive to measurement noise, with only minimal differences between methods. Reliabilities were moderate for subjective ratings but poor for skin conductance responses. All indices of fear generalization were unrelated to anxiety-related traits.ConclusionsOverall, a more comprehensive discussion of conceptual and methodological issues is needed to enable informed decisions about how to reliably and validly estimate fear generalization and its relationship with anxiety-related traits or clinical symptoms
Exploring the environmental impacts of wind turbines in forested areas: challenges, research gaps, and recommendations
No full textAs countries strive to meet emissions targets and satisfy high energy demands, the expansion of wind energy is increasingly being considered in forested regions. These areas, particularly those located on mountain ridges, might offer substantial wind resources at significant heights above the forest canopy. However, the dual role of forests in climate protection and biodiversity conservation makes the installation of wind turbines in these areas a subject of ongoing debate. This presents a clear dichotomy in densely populated regions such as Central Europe, where the choice often lies between exploiting natural environments or proximity to human settlements for wind energy development. This presentation delves into the impacts of wind turbines on forested ecosystems, critically reviewing the quality, focus, and execution of international scientific studies conducted over the past 15 years. By highlighting deficiencies and identifying research gaps, the presentation reveals that much of the current research is geographically and topically biased, often focusing on prominent issues, such as the direct mortality of birds and bats, which may not necessarily be the most severe. Many findings are case-specific and lack generalizability due to the absence of standardized, before-after control-impact (BACI) long-term studies. Furthermore, the impacts of wind energy installations must be evaluated within the context of other anthropogenic pressures, alongside the benefits of wind energy with respect to biodiversity. By implementing suitable, site-specific measures, potential conflicts can be minimized, laying the groundwork for socially acceptable, efficient, and sustainable wind energy expansion. This critical overview seeks to underscore the importance of comprehensive research efforts that encompass both ecological impacts and the broader environmental and social context, ultimately contributing to informed decision-making in wind energy policy
Synthesis, crystal structure, and optical properties of the broadband emitting [HSC(NH2)2]3PbBr5
No full textHerein, the experimental results on [HSC(NH2)2)]3PbBr5 (P21/c, a = 19.074(4), b = 9.2765(19), c = 11.980(2) Å, β = 106.53(3)°) are described. The crystal structure is composed of 1D chains of [PbBr6] octahedra sharing common corners. Therefore, the structure can be derived from the perovskite structure by cutting out 1D chains from the 3D network. The compound exhibits an indirect bandgap of ≈3.5 eV. The room temperature UV–Vis reflectance spectra additionally shows a strong excitation peak at around 3.2 eV. Under UV-light, [HSC(NH2)2)]3PbBr5 exhibits a strong and broad (full width at half maximum: ≈165 nm) white light luminescence. The experimental results are supported by density functional theory calculations
Wavelength-tunable femtosecond pulsed laser for the characterisation of solid-state sensors
No full textThe Two-Photon Absorption (TPA) process provides an excellent method for the characterisation of solid-state sensors due to its intrinsic 3D resolution for the excitation of electron-hole pairs. This paper presents the commissioning of a system composed of a Light Conversion PHAROS laser read out with an ORPHEUS optical parametric amplifier with tuneable output wavelength across 310–16000 nm. This is one of the few facilities suitable for particle physics detector applications with a very wide wavelength range and ultra short pulses. The voxel characterisation shows a Rayleigh length of 12.20 ± 0.47 μm and the beam radius at the waist of 1.53 ± 0.04 μm. Initial measurements with silicon and diamond samples are described. The apparatus is characterised with both devices, demonstrating the expected quadratic dependency with the energy per pulse, and different models are presented to explain the signal generated due to reflection. The signal generated in the silicon diode is in good agreement with one dimension voxel model predictions
Light and elevated temperature induced degradation: defect engineering in boron- and gallium-doped silicon solar cells
No full textLeTID (light and elevated temperature induced degradation) ist ein Phänomen, dasauf einen metastabilen Defekt in Siliziumsolarzellen zurückgeht, der unter Beleuchtung und bei erhöhten Temperaturen auftritt und die Effizienz der Zelle um bis zu 10% verringert. Obwohl die genaue Struktur des Defekts noch unbekannt ist, besteht Konsens darüber, dass Wasserstoff an seiner Entstehung beteiligt ist. Die Hauptquelle von Wasserstoff in Siliziumsolarzellen sind die wasserstoffhaltigen Passivierungsschichten, die bei der Herstellung auf die Siliziumoberfläche aufgebracht werden. Bei hohen Temperaturen steigen die Löslichkeit und Diffusivität von Wasserstoff in Silizium, wodurch dieser aus den dielektrischen Schichten ins Silizium diffundiert und sich dort anlagert.Solche erhöhten Temperaturen (700-830 °C) werden im letzten Herstellungsschritt einer Solarzelle erreicht, um die Metallisierung und das Silizium elektrisch zu verbinden.In dieser Arbeit wurde der Einfluss verschiedener Prozessparameter auf LeTID anLebensdauerproben untersucht. In der Literatur wurde gezeigt, dass durch eine Verringerung der maximalen Temperatur während der Kontaktausbildung LeTID in Bor-dotierten Siliziumwafern verhindert werden kann. In dieser Arbeit wird jedoch gezeigt, dass diese Methode bei Gallium-dotierten Proben deutlich weniger effektiv ist. Eine weitere Methode zur Reduzierung des Wasserstoffgehalts im Silizium besteht in der Änderung der Zusammensetzung der dielektrischen Schichten. Wird eine wasserstoffreiche Schicht direkt auf das Silizium aufgebracht, kann der Wasserstoff leicht in das Silizium diffundieren. Hier wird gezeigt, dass bereits eine 5 nm dicke Zwischenschicht aus Aluminiumoxid als Diffusionsbarriere fungiert und LeTID stark unterdrückt.Eine weitere Methode zur Unterdrückung von LeTID wurde in dieser Arbeit besonders detailliert untersucht und zur Anwendungsreife in der passivated emitter and rear cell (PERC)-Solarzellenproduktion entwickelt. Die Technik beruht auf einer Anpassung des Temperaturverlaufs bei der Kontaktausbildung. Im Standardprozess kühlt eine Solarzelle um etwa 70 K/s ab, nachdem sie ihre Maximaltemperatur erreicht hat. Dadurch sinkt die Diffusivität des Wasserstoffs so schnell, dass dieser nicht auf die ebenfalls verringerte Löslichkeit reagieren kann. Dies führt in der fertigen Solarzelle zu einerWasserstoffkonzentration, die weit über der Löslichkeitsgrenze von Wasserstoff in Silizium bei Raumtemperatur liegt. In dieser Arbeit wird gezeigt, dass bereits eine Verringerung der Abkühlrate auf 50 K/s ausreicht, um LeTID in PERC-Solarzellen aus Bor-dotiertem Cz-, hpm- und SMART-Silizium signifikant zu reduzieren. Im Fall von industriellen Cz-PERC-Siliziumsolarzellen mit mittlerweile typischer Gallium-Dotierung eliminiert die Methode LeTID sogar vollständig. Zudem konnte nachgewiesen werden, dass die entwickelte Methode die initiale Effizienz der Solarzellen nicht signifikant beeinflusst und auch nach dem Temperatureintrag durch den Laminationsprozess eines Moduls weiterhin wirksam bleibt. Im Gegensatz zu bisherigen Methoden zur Vermeidung von LeTID sind keine zusätzlichen Prozessschritte in der Zellherstellung erforderlich.Üblicherweise wird eine Zelle auf LeTID getestet, indem sie für 1100 Stunden erhöhter Temperatur und Beleuchtung ausgesetzt wird. Um die Testzeit zu verkürzen, wird hier eine Methode vorgestellt, die bereits nach 40 Minuten vergleichbare Ergebnisse liefert, indem die Temperatur und die Beleuchtung weiter erhöht werden. Zur Realisierung dieser Bedingungen wurde im Rahmen dieser Arbeit ein Degradationsteststand entwickelt.LeTID (light and elevated temperature induced degradation) is a phenomenon based on a metastable defect in silicon solar cells that occurs under illumination and at elevated temperatures, reducing the cell's efficiency by up to 10%. Although the exact structure of the defect remains unknown, there is consensus that hydrogen is involved in its formation. The main source of hydrogen in silicon solar cells are hydrogen-containing dielectric passivation layers that are deposited on the silicon surface during the manufacturing process. At elevated temperatures, the solubility and diffusivity of hydrogen in silicon increase, allowing it to diffuse from the dielectric layers into the silicon and accumulate there. Such elevated temperatures (700°C to 830°C) are reached in the final manufacturing step of a solar cell to electrically connect the metallization and the silicon.In this work, the influence of different process parameters on LeTID was investigated using lifetime samples. In the literature, it has been shown that by reducing the maximum temperature during contact formation, LeTID can be prevented in boron-doped silicon wafers. However, it is demonstrated in this work that this method is significantly less effective for gallium-doped samples. Another method for reducing the hydrogen content in silicon involves changing the composition of the dielectric layers. If a hydrogen-rich silicon nitride layer is applied directly to the silicon, hydrogen can easily diffuse into the silicon. It is shown here that even a 5 nm thick intermediate layer of aluminum oxide acts as a diffusion barrier and strongly suppresses LeTID.Another method for suppressing LeTID was investigated more intensively in this work and developed to application maturity in passivated emitter and rear cell (PERC) solar cell production. The technique is based on adjusting the temperature profile during contact formation. In the standard process, the solar cell cools down at a rate of about 70 K/s after reaching its maximum temperature. As a result, the diffusivity of hydrogen decreases so quickly that it cannot respond to the also decreased solubility. This leads to a hydrogen concentration in the finished solar cell that is far above the solubility limit of hydrogen in silicon at room temperature. This work demonstrates that merely reducing the cooling rate to 50 K/s is sufficient to significantly reduce LeTID in PERC solar cells made from boron-doped Cz, hpm, and SMART silicon. In the case of industrial Cz-PERC silicon solar cells with a now typical gallium-doping, the method completely eliminates LeTID. Furthermore, it has been shown that the developed method does not significantly affect the initial efficiency of the solar cells and remains effective even after the temperature input from a module lamination process. Unlike previous methods for avoiding LeTID, no additional process steps are required in cell manufacturing.Typically, a cell is tested for LeTID by exposing it to elevated temperature and illumination for 1100 hours. To shorten the test duration, a method is presented here that delivers comparable results after just 40 minutes by further increasing both temperature and illumination. To realize these conditions, a degradation test stand was developed as part of this work
Corrigendum to GRADE guidance 39: using GRADE-ADOLOPMENT to adopt, adapt or create contextualized recommendations from source guidelines and evidence syntheses [Journal of Clinical Epidemiology 81 (2024) 111494]
No full textSex differences in attentional visual processing but not in plasticity-related modulation of visually evoked potentials
No full textImpaired neuroplasticity is a core feature underlying many psychiatric disorders. Long-term potentiation (LTP)-like modulation of visually evoked potentials (VEPs), measured via EEG, represents a promising approach to assess plasticity in humans. Recent evidence indicates potential sex differences in VEP-based plasticity. This study investigated sex differences in visual cortical processing and plasticity by quantifying LTP-like modulation of VEPs. We analysed 96 available recordings from 61 women (mean age = 26.53 ± 6.87 years) and 35 men (mean age = 28.77 ± 8.63 years). VEPs were elicited using a checkerboard reversal stimulus (20 s at 2 Hz), presented before and after a 10-minute visual modulation. Post-modulation VEPs were recorded at 2, 8, 12, 18, 22, and 28 min. Amplitude changes from baseline to post-modulation were assessed. Predefined VEP components were analysed using linear mixed-effects models (LMEM), and time-resolved sex differences were evaluated via cluster-based permutation testing. LTP-like modulation was evident in early VEP components—specifically C1, P1, and P1N1 peak-to-peak amplitude indicating dynamic changes in early visual processing from 2 to 8 min post-stimulation. LMEM did not reveal any sex-specific effects in these components. However, time-course analyses identified discrete, significant sex differences in late VEP components in late VEP components at baseline (350–390 ms; p = .043) and 18 min post-modulation (388–426 ms; p = .048). Our findings demonstrate robust LTP-like modulation in early VEP components independent of sex. Subtle sex differences emerged in late, unmodulated VEP components (350–426 ms), likely reflecting variations in attention-related processing rather than plasticity per se